Positive electrode plate for nickel-hydrogen cell

Abstract

The positive electrode plate is a plate material which is formed by filling a foaming nickel substrate with a paste-like kneaded substance containing nickel hydroxide, and drying and pressure forming the substrate. The foaming nickel substrate is prepared by removing a plate foaming core material of urethane foam or the like after nickel-plating the foaming core material. First, the mass per unit area of nickel in the foaming nickel substrate is set to be 0.5 kg/m 2 or more, so that the ohmic resistance of the foaming nickel substrate can be lower than those of conventional foaming nickel substrates. In addition, the upper limit of the mass per unit area of nickel in the foaming nickel substrate is set to be 1.1 kg/m 2 , so that it is possible to prevent the reduction of the energy density from exceeding the effect of the reduction of the ohmic resistance of the foaming nickel substrate.

What is claimed is:  
     
       1. A positive electrode plate for a nickel-hydrogen cell, said positive electrode plate being formed of a plate material comprising: 
       a foamed nickel substrate formed by removing a plate foamed core material after nickel-plating the foamed core material while tension is applied to said foamed core material in a specific direction; and  
       a kneaded substance containing nickel hydroxide as a principal component, said kneaded substance being filled in said foamed nickel substrate,  
       wherein said plate material is cut so as to have a predetermined dimension, and cylindrically wound such that a direction of winding tension is substantially perpendicular to the direction of tension applied to said foamed core material.  
     
     
       2. The positive electrode plate according to  claim 1 , wherein said foamed nickel substrate has a maximum elongation percentage in a first direction and a minimum elongation percentage in a second direction, said maximum elongation percentage being at least twice said minimum elongation percentage. 
     
     
       3. The positive electrode plate according to  claim 1 , wherein said foamed core material has a porous structure having a directional property such that said porous structure is elongated in a specific direction. 
     
     
       4. A positive electrode plate for a nickel-hydrogen cell, said positive electrode plate being formed of a plate material comprising: 
       a foamed nickel substrate formed by removing a plate foamed core material after nickel-plating in the foamed core material; and  
       a kneaded substance containing nickel hydroxide as a principal component, said kneaded substance being filled in said foamed nickel substrate,  
       wherein said plate material is cut so as to have a predetermined dimension, and cylindrically wound in a winding direction substantially corresponding to a first direction in which said foamed nickel substrate has a maximum elongation percentage.  
     
     
       5. The positive electrode plate according to  claim 4 , wherein said foamed nickel substrate has a minimum elongation percentage in a second direction, said maximum elongation percentage being at least twice said minimum elongation percentage. 
     
     
       6. The positive electrode plate according to  claim 4 , wherein said foamed core material has a porous structure having a directional property such that said porous structure is elongated in a specific direction.